Theoretical study of ferulic acid dimer derivatives: bond dissociation enthalpy, spin density, and HOMO-LUMO analysis

This article describes a theoretical study of four ferulic acid dimer derivatives, in order to obtain information about their reactivity towards free radicals and their antioxidant capacity. The results, of the studied structures, have been carefully studied by analyzing their molecular orbitals, spin density distribution, and bond dissociation enthalpies (BDEs), using the PBE0/6-311++G(2d,2p) method. Our results were compared with those already obtained experimentally in the literature by Garcia-Conesa and co-workers, such comparisons show good agreement. These comparisons show that the results obtained from molecular orbitals and spin density distribution provide the most information about these molecular systems. The role of the OH group from the carboxyl groups, in all structures, is not very significant due to low electron delocalization, which is only located in the R-COO center dot fragment.